/* eslint-disable */

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  // Already initialized, skip
} else {
  window.__WEB_FETCHER_HELPER_INITIALIZED__ = true;

  /*
   * Copyright (c) 2010 Arc90 Inc
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */

  /*
   * This code is heavily based on Arc90's readability.js (1.7.1) script
   * available at: http://code.google.com/p/arc90labs-readability
   */

  /**
   * Public constructor.
   * @param {HTMLDocument} doc     The document to parse.
   * @param {Object}       options The options object.
   */
  function Readability(doc, options) {
    // In some older versions, people passed a URI as the first argument. Cope:
    if (options && options.documentElement) {
      doc = options;
      options = arguments[2];
    } else if (!doc || !doc.documentElement) {
      throw new Error('First argument to Readability constructor should be a document object.');
    }
    options = options || {};

    this._doc = doc;
    this._docJSDOMParser = this._doc.firstChild.__JSDOMParser__;
    this._articleTitle = null;
    this._articleByline = null;
    this._articleDir = null;
    this._articleSiteName = null;
    this._attempts = [];
    this._metadata = {};

    // Configurable options
    this._debug = !!options.debug;
    this._maxElemsToParse = options.maxElemsToParse || this.DEFAULT_MAX_ELEMS_TO_PARSE;
    this._nbTopCandidates = options.nbTopCandidates || this.DEFAULT_N_TOP_CANDIDATES;
    this._charThreshold = options.charThreshold || this.DEFAULT_CHAR_THRESHOLD;
    this._classesToPreserve = this.CLASSES_TO_PRESERVE.concat(options.classesToPreserve || []);
    this._keepClasses = !!options.keepClasses;
    this._serializer =
      options.serializer ||
      function (el) {
        return el.innerHTML;
      };
    this._disableJSONLD = !!options.disableJSONLD;
    this._allowedVideoRegex = options.allowedVideoRegex || this.REGEXPS.videos;
    this._linkDensityModifier = options.linkDensityModifier || 0;

    // Start with all flags set
    this._flags =
      this.FLAG_STRIP_UNLIKELYS | this.FLAG_WEIGHT_CLASSES | this.FLAG_CLEAN_CONDITIONALLY;

    // Control whether log messages are sent to the console
    if (this._debug) {
      let logNode = function (node) {
        if (node.nodeType == node.TEXT_NODE) {
          return `${node.nodeName} ("${node.textContent}")`;
        }
        let attrPairs = Array.from(node.attributes || [], function (attr) {
          return `${attr.name}="${attr.value}"`;
        }).join(' ');
        return `<${node.localName} ${attrPairs}>`;
      };
      this.log = function () {
        if (typeof console !== 'undefined') {
          let args = Array.from(arguments, (arg) => {
            if (arg && arg.nodeType == this.ELEMENT_NODE) {
              return logNode(arg);
            }
            return arg;
          });
          args.unshift('Reader: (Readability)');

          // Debug logging removed
        } else if (typeof dump !== 'undefined') {
          /* global dump */
          var msg = Array.prototype.map
            .call(arguments, function (x) {
              return x && x.nodeName ? logNode(x) : x;
            })
            .join(' ');
          dump('Reader: (Readability) ' + msg + '\n');
        }
      };
    } else {
      this.log = function () {};
    }
  }

  Readability.prototype = {
    FLAG_STRIP_UNLIKELYS: 0x1,
    FLAG_WEIGHT_CLASSES: 0x2,
    FLAG_CLEAN_CONDITIONALLY: 0x4,

    // https://developer.mozilla.org/en-US/docs/Web/API/Node/nodeType
    ELEMENT_NODE: 1,
    TEXT_NODE: 3,

    // Max number of nodes supported by this parser. Default: 0 (no limit)
    DEFAULT_MAX_ELEMS_TO_PARSE: 0,

    // The number of top candidates to consider when analysing how
    // tight the competition is among candidates.
    DEFAULT_N_TOP_CANDIDATES: 5,

    // Element tags to score by default.
    DEFAULT_TAGS_TO_SCORE: 'section,h2,h3,h4,h5,h6,p,td,pre'.toUpperCase().split(','),

    // The default number of chars an article must have in order to return a result
    DEFAULT_CHAR_THRESHOLD: 500,

    // All of the regular expressions in use within readability.
    // Defined up here so we don't instantiate them repeatedly in loops.
    REGEXPS: {
      // NOTE: These two regular expressions are duplicated in
      // Readability-readerable.js. Please keep both copies in sync.
      unlikelyCandidates:
        /-ad-|ai2html|banner|breadcrumbs|combx|comment|community|cover-wrap|disqus|extra|footer|gdpr|header|legends|menu|related|remark|replies|rss|shoutbox|sidebar|skyscraper|social|sponsor|supplemental|ad-break|agegate|pagination|pager|popup|yom-remote/i,
      okMaybeItsACandidate: /and|article|body|column|content|main|shadow/i,

      positive:
        /article|body|content|entry|hentry|h-entry|main|page|pagination|post|text|blog|story/i,
      negative:
        /-ad-|hidden|^hid$| hid$| hid |^hid |banner|combx|comment|com-|contact|footer|gdpr|masthead|media|meta|outbrain|promo|related|scroll|share|shoutbox|sidebar|skyscraper|sponsor|shopping|tags|widget/i,
      extraneous:
        /print|archive|comment|discuss|e[\-]?mail|share|reply|all|login|sign|single|utility/i,
      byline: /byline|author|dateline|writtenby|p-author/i,
      replaceFonts: /<(\/?)font[^>]*>/gi,
      normalize: /\s{2,}/g,
      videos:
        /\/\/(www\.)?((dailymotion|youtube|youtube-nocookie|player\.vimeo|v\.qq)\.com|(archive|upload\.wikimedia)\.org|player\.twitch\.tv)/i,
      shareElements: /(\b|_)(share|sharedaddy)(\b|_)/i,
      nextLink: /(next|weiter|continue|>([^\|]|$)|»([^\|]|$))/i,
      prevLink: /(prev|earl|old|new|<|«)/i,
      tokenize: /\W+/g,
      whitespace: /^\s*$/,
      hasContent: /\S$/,
      hashUrl: /^#.+/,
      srcsetUrl: /(\S+)(\s+[\d.]+[xw])?(\s*(?:,|$))/g,
      b64DataUrl: /^data:\s*([^\s;,]+)\s*;\s*base64\s*,/i,
      // Commas as used in Latin, Sindhi, Chinese and various other scripts.
      // see: https://en.wikipedia.org/wiki/Comma#Comma_variants
      commas: /\u002C|\u060C|\uFE50|\uFE10|\uFE11|\u2E41|\u2E34|\u2E32|\uFF0C/g,
      // See: https://schema.org/Article
      jsonLdArticleTypes:
        /^Article|AdvertiserContentArticle|NewsArticle|AnalysisNewsArticle|AskPublicNewsArticle|BackgroundNewsArticle|OpinionNewsArticle|ReportageNewsArticle|ReviewNewsArticle|Report|SatiricalArticle|ScholarlyArticle|MedicalScholarlyArticle|SocialMediaPosting|BlogPosting|LiveBlogPosting|DiscussionForumPosting|TechArticle|APIReference$/,
      // used to see if a node's content matches words commonly used for ad blocks or loading indicators
      adWords: /^(ad(vertising|vertisement)?|pub(licité)?|werb(ung)?|广告|Реклама|Anuncio)$/iu,
      loadingWords: /^((loading|正在加载|Загрузка|chargement|cargando)(…|\.\.\.)?)$/iu,
    },

    UNLIKELY_ROLES: [
      'menu',
      'menubar',
      'complementary',
      'navigation',
      'alert',
      'alertdialog',
      'dialog',
    ],

    DIV_TO_P_ELEMS: new Set(['BLOCKQUOTE', 'DL', 'DIV', 'IMG', 'OL', 'P', 'PRE', 'TABLE', 'UL']),

    ALTER_TO_DIV_EXCEPTIONS: ['DIV', 'ARTICLE', 'SECTION', 'P', 'OL', 'UL'],

    PRESENTATIONAL_ATTRIBUTES: [
      'align',
      'background',
      'bgcolor',
      'border',
      'cellpadding',
      'cellspacing',
      'frame',
      'hspace',
      'rules',
      'style',
      'valign',
      'vspace',
    ],

    DEPRECATED_SIZE_ATTRIBUTE_ELEMS: ['TABLE', 'TH', 'TD', 'HR', 'PRE'],

    // The commented out elements qualify as phrasing content but tend to be
    // removed by readability when put into paragraphs, so we ignore them here.
    PHRASING_ELEMS: [
      // "CANVAS", "IFRAME", "SVG", "VIDEO",
      'ABBR',
      'AUDIO',
      'B',
      'BDO',
      'BR',
      'BUTTON',
      'CITE',
      'CODE',
      'DATA',
      'DATALIST',
      'DFN',
      'EM',
      'EMBED',
      'I',
      'IMG',
      'INPUT',
      'KBD',
      'LABEL',
      'MARK',
      'MATH',
      'METER',
      'NOSCRIPT',
      'OBJECT',
      'OUTPUT',
      'PROGRESS',
      'Q',
      'RUBY',
      'SAMP',
      'SCRIPT',
      'SELECT',
      'SMALL',
      'SPAN',
      'STRONG',
      'SUB',
      'SUP',
      'TEXTAREA',
      'TIME',
      'VAR',
      'WBR',
    ],

    // These are the classes that readability sets itself.
    CLASSES_TO_PRESERVE: ['page'],

    // These are the list of HTML entities that need to be escaped.
    HTML_ESCAPE_MAP: {
      lt: '<',
      gt: '>',
      amp: '&',
      quot: '"',
      apos: "'",
    },

    /**
     * Run any post-process modifications to article content as necessary.
     *
     * @param Element
     * @return void
     **/
    _postProcessContent(articleContent) {
      // Readability cannot open relative uris so we convert them to absolute uris.
      this._fixRelativeUris(articleContent);

      this._simplifyNestedElements(articleContent);

      if (!this._keepClasses) {
        // Remove classes.
        this._cleanClasses(articleContent);
      }
    },

    /**
     * Iterates over a NodeList, calls `filterFn` for each node and removes node
     * if function returned `true`.
     *
     * If function is not passed, removes all the nodes in node list.
     *
     * @param NodeList nodeList The nodes to operate on
     * @param Function filterFn the function to use as a filter
     * @return void
     */
    _removeNodes(nodeList, filterFn) {
      // Avoid ever operating on live node lists.
      if (this._docJSDOMParser && nodeList._isLiveNodeList) {
        throw new Error('Do not pass live node lists to _removeNodes');
      }
      for (var i = nodeList.length - 1; i >= 0; i--) {
        var node = nodeList[i];
        var parentNode = node.parentNode;
        if (parentNode) {
          if (!filterFn || filterFn.call(this, node, i, nodeList)) {
            parentNode.removeChild(node);
          }
        }
      }
    },

    /**
     * Iterates over a NodeList, and calls _setNodeTag for each node.
     *
     * @param NodeList nodeList The nodes to operate on
     * @param String newTagName the new tag name to use
     * @return void
     */
    _replaceNodeTags(nodeList, newTagName) {
      // Avoid ever operating on live node lists.
      if (this._docJSDOMParser && nodeList._isLiveNodeList) {
        throw new Error('Do not pass live node lists to _replaceNodeTags');
      }
      for (const node of nodeList) {
        this._setNodeTag(node, newTagName);
      }
    },

    /**
     * Iterate over a NodeList, which doesn't natively fully implement the Array
     * interface.
     *
     * For convenience, the current object context is applied to the provided
     * iterate function.
     *
     * @param  NodeList nodeList The NodeList.
     * @param  Function fn       The iterate function.
     * @return void
     */
    _forEachNode(nodeList, fn) {
      Array.prototype.forEach.call(nodeList, fn, this);
    },

    /**
     * Iterate over a NodeList, and return the first node that passes
     * the supplied test function
     *
     * For convenience, the current object context is applied to the provided
     * test function.
     *
     * @param  NodeList nodeList The NodeList.
     * @param  Function fn       The test function.
     * @return void
     */
    _findNode(nodeList, fn) {
      return Array.prototype.find.call(nodeList, fn, this);
    },

    /**
     * Iterate over a NodeList, return true if any of the provided iterate
     * function calls returns true, false otherwise.
     *
     * For convenience, the current object context is applied to the
     * provided iterate function.
     *
     * @param  NodeList nodeList The NodeList.
     * @param  Function fn       The iterate function.
     * @return Boolean
     */
    _someNode(nodeList, fn) {
      return Array.prototype.some.call(nodeList, fn, this);
    },

    /**
     * Iterate over a NodeList, return true if all of the provided iterate
     * function calls return true, false otherwise.
     *
     * For convenience, the current object context is applied to the
     * provided iterate function.
     *
     * @param  NodeList nodeList The NodeList.
     * @param  Function fn       The iterate function.
     * @return Boolean
     */
    _everyNode(nodeList, fn) {
      return Array.prototype.every.call(nodeList, fn, this);
    },

    _getAllNodesWithTag(node, tagNames) {
      if (node.querySelectorAll) {
        return node.querySelectorAll(tagNames.join(','));
      }
      return [].concat.apply(
        [],
        tagNames.map(function (tag) {
          var collection = node.getElementsByTagName(tag);
          return Array.isArray(collection) ? collection : Array.from(collection);
        }),
      );
    },

    /**
     * Removes the class="" attribute from every element in the given
     * subtree, except those that match CLASSES_TO_PRESERVE and
     * the classesToPreserve array from the options object.
     *
     * @param Element
     * @return void
     */
    _cleanClasses(node) {
      var classesToPreserve = this._classesToPreserve;
      var className = (node.getAttribute('class') || '')
        .split(/\s+/)
        .filter((cls) => classesToPreserve.includes(cls))
        .join(' ');

      if (className) {
        node.setAttribute('class', className);
      } else {
        node.removeAttribute('class');
      }

      for (node = node.firstElementChild; node; node = node.nextElementSibling) {
        this._cleanClasses(node);
      }
    },

    /**
     * Tests whether a string is a URL or not.
     *
     * @param {string} str The string to test
     * @return {boolean} true if str is a URL, false if not
     */
    _isUrl(str) {
      try {
        new URL(str);
        return true;
      } catch {
        return false;
      }
    },
    /**
     * Converts each <a> and <img> uri in the given element to an absolute URI,
     * ignoring #ref URIs.
     *
     * @param Element
     * @return void
     */
    _fixRelativeUris(articleContent) {
      var baseURI = this._doc.baseURI;
      var documentURI = this._doc.documentURI;
      function toAbsoluteURI(uri) {
        // Leave hash links alone if the base URI matches the document URI:
        if (baseURI == documentURI && uri.charAt(0) == '#') {
          return uri;
        }

        // Otherwise, resolve against base URI:
        try {
          return new URL(uri, baseURI).href;
        } catch (ex) {
          // Something went wrong, just return the original:
        }
        return uri;
      }

      var links = this._getAllNodesWithTag(articleContent, ['a']);
      this._forEachNode(links, function (link) {
        var href = link.getAttribute('href');
        if (href) {
          // Remove links with javascript: URIs, since
          // they won't work after scripts have been removed from the page.
          if (href.indexOf('javascript:') === 0) {
            // if the link only contains simple text content, it can be converted to a text node
            if (link.childNodes.length === 1 && link.childNodes[0].nodeType === this.TEXT_NODE) {
              var text = this._doc.createTextNode(link.textContent);
              link.parentNode.replaceChild(text, link);
            } else {
              // if the link has multiple children, they should all be preserved
              var container = this._doc.createElement('span');
              while (link.firstChild) {
                container.appendChild(link.firstChild);
              }
              link.parentNode.replaceChild(container, link);
            }
          } else {
            link.setAttribute('href', toAbsoluteURI(href));
          }
        }
      });

      var medias = this._getAllNodesWithTag(articleContent, [
        'img',
        'picture',
        'figure',
        'video',
        'audio',
        'source',
      ]);

      this._forEachNode(medias, function (media) {
        var src = media.getAttribute('src');
        var poster = media.getAttribute('poster');
        var srcset = media.getAttribute('srcset');

        if (src) {
          media.setAttribute('src', toAbsoluteURI(src));
        }

        if (poster) {
          media.setAttribute('poster', toAbsoluteURI(poster));
        }

        if (srcset) {
          var newSrcset = srcset.replace(this.REGEXPS.srcsetUrl, function (_, p1, p2, p3) {
            return toAbsoluteURI(p1) + (p2 || '') + p3;
          });

          media.setAttribute('srcset', newSrcset);
        }
      });
    },

    _simplifyNestedElements(articleContent) {
      var node = articleContent;

      while (node) {
        if (
          node.parentNode &&
          ['DIV', 'SECTION'].includes(node.tagName) &&
          !(node.id && node.id.startsWith('readability'))
        ) {
          if (this._isElementWithoutContent(node)) {
            node = this._removeAndGetNext(node);
            continue;
          } else if (
            this._hasSingleTagInsideElement(node, 'DIV') ||
            this._hasSingleTagInsideElement(node, 'SECTION')
          ) {
            var child = node.children[0];
            for (var i = 0; i < node.attributes.length; i++) {
              child.setAttributeNode(node.attributes[i].cloneNode());
            }
            node.parentNode.replaceChild(child, node);
            node = child;
            continue;
          }
        }

        node = this._getNextNode(node);
      }
    },

    /**
     * Get the article title as an H1.
     *
     * @return string
     **/
    _getArticleTitle() {
      var doc = this._doc;
      var curTitle = '';
      var origTitle = '';

      try {
        curTitle = origTitle = doc.title.trim();

        // If they had an element with id "title" in their HTML
        if (typeof curTitle !== 'string') {
          curTitle = origTitle = this._getInnerText(doc.getElementsByTagName('title')[0]);
        }
      } catch (e) {
        /* ignore exceptions setting the title. */
      }

      var titleHadHierarchicalSeparators = false;
      function wordCount(str) {
        return str.split(/\s+/).length;
      }

      // If there's a separator in the title, first remove the final part
      if (/ [\|\-\\\/>»] /.test(curTitle)) {
        titleHadHierarchicalSeparators = / [\\\/>»] /.test(curTitle);
        let allSeparators = Array.from(origTitle.matchAll(/ [\|\-\\\/>»] /gi));
        curTitle = origTitle.substring(0, allSeparators.pop().index);

        // If the resulting title is too short, remove the first part instead:
        if (wordCount(curTitle) < 3) {
          curTitle = origTitle.replace(/^[^\|\-\\\/>»]*[\|\-\\\/>»]/gi, '');
        }
      } else if (curTitle.includes(': ')) {
        // Check if we have an heading containing this exact string, so we
        // could assume it's the full title.
        var headings = this._getAllNodesWithTag(doc, ['h1', 'h2']);
        var trimmedTitle = curTitle.trim();
        var match = this._someNode(headings, function (heading) {
          return heading.textContent.trim() === trimmedTitle;
        });

        // If we don't, let's extract the title out of the original title string.
        if (!match) {
          curTitle = origTitle.substring(origTitle.lastIndexOf(':') + 1);

          // If the title is now too short, try the first colon instead:
          if (wordCount(curTitle) < 3) {
            curTitle = origTitle.substring(origTitle.indexOf(':') + 1);
            // But if we have too many words before the colon there's something weird
            // with the titles and the H tags so let's just use the original title instead
          } else if (wordCount(origTitle.substr(0, origTitle.indexOf(':'))) > 5) {
            curTitle = origTitle;
          }
        }
      } else if (curTitle.length > 150 || curTitle.length < 15) {
        var hOnes = doc.getElementsByTagName('h1');

        if (hOnes.length === 1) {
          curTitle = this._getInnerText(hOnes[0]);
        }
      }

      curTitle = curTitle.trim().replace(this.REGEXPS.normalize, ' ');
      // If we now have 4 words or fewer as our title, and either no
      // 'hierarchical' separators (\, /, > or ») were found in the original
      // title or we decreased the number of words by more than 1 word, use
      // the original title.
      var curTitleWordCount = wordCount(curTitle);
      if (
        curTitleWordCount <= 4 &&
        (!titleHadHierarchicalSeparators ||
          curTitleWordCount != wordCount(origTitle.replace(/[\|\-\\\/>»]+/g, '')) - 1)
      ) {
        curTitle = origTitle;
      }

      return curTitle;
    },

    /**
     * Prepare the HTML document for readability to scrape it.
     * This includes things like stripping javascript, CSS, and handling terrible markup.
     *
     * @return void
     **/
    _prepDocument() {
      var doc = this._doc;

      // Remove all style tags in head
      this._removeNodes(this._getAllNodesWithTag(doc, ['style']));

      if (doc.body) {
        this._replaceBrs(doc.body);
      }

      this._replaceNodeTags(this._getAllNodesWithTag(doc, ['font']), 'SPAN');
    },

    /**
     * Finds the next node, starting from the given node, and ignoring
     * whitespace in between. If the given node is an element, the same node is
     * returned.
     */
    _nextNode(node) {
      var next = node;
      while (
        next &&
        next.nodeType != this.ELEMENT_NODE &&
        this.REGEXPS.whitespace.test(next.textContent)
      ) {
        next = next.nextSibling;
      }
      return next;
    },

    /**
     * Replaces 2 or more successive <br> elements with a single <p>.
     * Whitespace between <br> elements are ignored. For example:
     *   <div>foo<br>bar<br> <br><br>abc</div>
     * will become:
     *   <div>foo<br>bar<p>abc</p></div>
     */
    _replaceBrs(elem) {
      this._forEachNode(this._getAllNodesWithTag(elem, ['br']), function (br) {
        var next = br.nextSibling;

        // Whether 2 or more <br> elements have been found and replaced with a
        // <p> block.
        var replaced = false;

        // If we find a <br> chain, remove the <br>s until we hit another node
        // or non-whitespace. This leaves behind the first <br> in the chain
        // (which will be replaced with a <p> later).
        while ((next = this._nextNode(next)) && next.tagName == 'BR') {
          replaced = true;
          var brSibling = next.nextSibling;
          next.remove();
          next = brSibling;
        }

        // If we removed a <br> chain, replace the remaining <br> with a <p>. Add
        // all sibling nodes as children of the <p> until we hit another <br>
        // chain.
        if (replaced) {
          var p = this._doc.createElement('p');
          br.parentNode.replaceChild(p, br);

          next = p.nextSibling;
          while (next) {
            // If we've hit another <br><br>, we're done adding children to this <p>.
            if (next.tagName == 'BR') {
              var nextElem = this._nextNode(next.nextSibling);
              if (nextElem && nextElem.tagName == 'BR') {
                break;
              }
            }

            if (!this._isPhrasingContent(next)) {
              break;
            }

            // Otherwise, make this node a child of the new <p>.
            var sibling = next.nextSibling;
            p.appendChild(next);
            next = sibling;
          }

          while (p.lastChild && this._isWhitespace(p.lastChild)) {
            p.lastChild.remove();
          }

          if (p.parentNode.tagName === 'P') {
            this._setNodeTag(p.parentNode, 'DIV');
          }
        }
      });
    },

    _setNodeTag(node, tag) {
      this.log('_setNodeTag', node, tag);
      if (this._docJSDOMParser) {
        node.localName = tag.toLowerCase();
        node.tagName = tag.toUpperCase();
        return node;
      }

      var replacement = node.ownerDocument.createElement(tag);
      while (node.firstChild) {
        replacement.appendChild(node.firstChild);
      }
      node.parentNode.replaceChild(replacement, node);
      if (node.readability) {
        replacement.readability = node.readability;
      }

      for (var i = 0; i < node.attributes.length; i++) {
        replacement.setAttributeNode(node.attributes[i].cloneNode());
      }
      return replacement;
    },

    /**
     * Prepare the article node for display. Clean out any inline styles,
     * iframes, forms, strip extraneous <p> tags, etc.
     *
     * @param Element
     * @return void
     **/
    _prepArticle(articleContent) {
      this._cleanStyles(articleContent);

      // Check for data tables before we continue, to avoid removing items in
      // those tables, which will often be isolated even though they're
      // visually linked to other content-ful elements (text, images, etc.).
      this._markDataTables(articleContent);

      this._fixLazyImages(articleContent);

      // Clean out junk from the article content
      this._cleanConditionally(articleContent, 'form');
      this._cleanConditionally(articleContent, 'fieldset');
      this._clean(articleContent, 'object');
      this._clean(articleContent, 'embed');
      this._clean(articleContent, 'footer');
      this._clean(articleContent, 'link');
      this._clean(articleContent, 'aside');

      // Clean out elements with little content that have "share" in their id/class combinations from final top candidates,
      // which means we don't remove the top candidates even they have "share".

      var shareElementThreshold = this.DEFAULT_CHAR_THRESHOLD;

      this._forEachNode(articleContent.children, function (topCandidate) {
        this._cleanMatchedNodes(topCandidate, function (node, matchString) {
          return (
            this.REGEXPS.shareElements.test(matchString) &&
            node.textContent.length < shareElementThreshold
          );
        });
      });

      this._clean(articleContent, 'iframe');
      this._clean(articleContent, 'input');
      this._clean(articleContent, 'textarea');
      this._clean(articleContent, 'select');
      this._clean(articleContent, 'button');
      this._cleanHeaders(articleContent);

      // Do these last as the previous stuff may have removed junk
      // that will affect these
      this._cleanConditionally(articleContent, 'table');
      this._cleanConditionally(articleContent, 'ul');
      this._cleanConditionally(articleContent, 'div');

      // replace H1 with H2 as H1 should be only title that is displayed separately
      this._replaceNodeTags(this._getAllNodesWithTag(articleContent, ['h1']), 'h2');

      // Remove extra paragraphs
      this._removeNodes(this._getAllNodesWithTag(articleContent, ['p']), function (paragraph) {
        // At this point, nasty iframes have been removed; only embedded video
        // ones remain.
        var contentElementCount = this._getAllNodesWithTag(paragraph, [
          'img',
          'embed',
          'object',
          'iframe',
        ]).length;
        return contentElementCount === 0 && !this._getInnerText(paragraph, false);
      });

      this._forEachNode(this._getAllNodesWithTag(articleContent, ['br']), function (br) {
        var next = this._nextNode(br.nextSibling);
        if (next && next.tagName == 'P') {
          br.remove();
        }
      });

      // Remove single-cell tables
      this._forEachNode(this._getAllNodesWithTag(articleContent, ['table']), function (table) {
        var tbody = this._hasSingleTagInsideElement(table, 'TBODY')
          ? table.firstElementChild
          : table;
        if (this._hasSingleTagInsideElement(tbody, 'TR')) {
          var row = tbody.firstElementChild;
          if (this._hasSingleTagInsideElement(row, 'TD')) {
            var cell = row.firstElementChild;
            cell = this._setNodeTag(
              cell,
              this._everyNode(cell.childNodes, this._isPhrasingContent) ? 'P' : 'DIV',
            );
            table.parentNode.replaceChild(cell, table);
          }
        }
      });
    },

    /**
     * Initialize a node with the readability object. Also checks the
     * className/id for special names to add to its score.
     *
     * @param Element
     * @return void
     **/
    _initializeNode(node) {
      node.readability = { contentScore: 0 };

      switch (node.tagName) {
        case 'DIV':
          node.readability.contentScore += 5;
          break;

        case 'PRE':
        case 'TD':
        case 'BLOCKQUOTE':
          node.readability.contentScore += 3;
          break;

        case 'ADDRESS':
        case 'OL':
        case 'UL':
        case 'DL':
        case 'DD':
        case 'DT':
        case 'LI':
        case 'FORM':
          node.readability.contentScore -= 3;
          break;

        case 'H1':
        case 'H2':
        case 'H3':
        case 'H4':
        case 'H5':
        case 'H6':
        case 'TH':
          node.readability.contentScore -= 5;
          break;
      }

      node.readability.contentScore += this._getClassWeight(node);
    },

    _removeAndGetNext(node) {
      var nextNode = this._getNextNode(node, true);
      node.remove();
      return nextNode;
    },

    /**
     * Traverse the DOM from node to node, starting at the node passed in.
     * Pass true for the second parameter to indicate this node itself
     * (and its kids) are going away, and we want the next node over.
     *
     * Calling this in a loop will traverse the DOM depth-first.
     *
     * @param {Element} node
     * @param {boolean} ignoreSelfAndKids
     * @return {Element}
     */
    _getNextNode(node, ignoreSelfAndKids) {
      // First check for kids if those aren't being ignored
      if (!ignoreSelfAndKids && node.firstElementChild) {
        return node.firstElementChild;
      }
      // Then for siblings...
      if (node.nextElementSibling) {
        return node.nextElementSibling;
      }
      // And finally, move up the parent chain *and* find a sibling
      // (because this is depth-first traversal, we will have already
      // seen the parent nodes themselves).
      do {
        node = node.parentNode;
      } while (node && !node.nextElementSibling);
      return node && node.nextElementSibling;
    },

    // compares second text to first one
    // 1 = same text, 0 = completely different text
    // works the way that it splits both texts into words and then finds words that are unique in second text
    // the result is given by the lower length of unique parts
    _textSimilarity(textA, textB) {
      var tokensA = textA.toLowerCase().split(this.REGEXPS.tokenize).filter(Boolean);
      var tokensB = textB.toLowerCase().split(this.REGEXPS.tokenize).filter(Boolean);
      if (!tokensA.length || !tokensB.length) {
        return 0;
      }
      var uniqTokensB = tokensB.filter((token) => !tokensA.includes(token));
      var distanceB = uniqTokensB.join(' ').length / tokensB.join(' ').length;
      return 1 - distanceB;
    },

    /**
     * Checks whether an element node contains a valid byline
     *
     * @param node {Element}
     * @param matchString {string}
     * @return boolean
     */
    _isValidByline(node, matchString) {
      var rel = node.getAttribute('rel');
      var itemprop = node.getAttribute('itemprop');
      var bylineLength = node.textContent.trim().length;

      return (
        (rel === 'author' ||
          (itemprop && itemprop.includes('author')) ||
          this.REGEXPS.byline.test(matchString)) &&
        !!bylineLength &&
        bylineLength < 100
      );
    },

    _getNodeAncestors(node, maxDepth) {
      maxDepth = maxDepth || 0;
      var i = 0,
        ancestors = [];
      while (node.parentNode) {
        ancestors.push(node.parentNode);
        if (maxDepth && ++i === maxDepth) {
          break;
        }
        node = node.parentNode;
      }
      return ancestors;
    },

    /***
     * grabArticle - Using a variety of metrics (content score, classname, element types), find the content that is
     *         most likely to be the stuff a user wants to read. Then return it wrapped up in a div.
     *
     * @param page a document to run upon. Needs to be a full document, complete with body.
     * @return Element
     **/

    _grabArticle(page) {
      this.log('**** grabArticle ****');
      var doc = this._doc;
      var isPaging = page !== null;
      page = page ? page : this._doc.body;

      // We can't grab an article if we don't have a page!
      if (!page) {
        this.log('No body found in document. Abort.');
        return null;
      }

      var pageCacheHtml = page.innerHTML;

      while (true) {
        this.log('Starting grabArticle loop');
        var stripUnlikelyCandidates = this._flagIsActive(this.FLAG_STRIP_UNLIKELYS);

        // First, node prepping. Trash nodes that look cruddy (like ones with the
        // class name "comment", etc), and turn divs into P tags where they have been
        // used inappropriately (as in, where they contain no other block level elements.)
        var elementsToScore = [];
        var node = this._doc.documentElement;

        let shouldRemoveTitleHeader = true;

        while (node) {
          if (node.tagName === 'HTML') {
            this._articleLang = node.getAttribute('lang');
          }

          var matchString = node.className + ' ' + node.id;

          if (!this._isProbablyVisible(node)) {
            this.log('Removing hidden node - ' + matchString);
            node = this._removeAndGetNext(node);
            continue;
          }

          // User is not able to see elements applied with both "aria-modal = true" and "role = dialog"
          if (node.getAttribute('aria-modal') == 'true' && node.getAttribute('role') == 'dialog') {
            node = this._removeAndGetNext(node);
            continue;
          }

          // If we don't have a byline yet check to see if this node is a byline; if it is store the byline and remove the node.
          if (
            !this._articleByline &&
            !this._metadata.byline &&
            this._isValidByline(node, matchString)
          ) {
            // Find child node matching [itemprop="name"] and use that if it exists for a more accurate author name byline
            var endOfSearchMarkerNode = this._getNextNode(node, true);
            var next = this._getNextNode(node);
            var itemPropNameNode = null;
            while (next && next != endOfSearchMarkerNode) {
              var itemprop = next.getAttribute('itemprop');
              if (itemprop && itemprop.includes('name')) {
                itemPropNameNode = next;
                break;
              } else {
                next = this._getNextNode(next);
              }
            }
            this._articleByline = (itemPropNameNode ?? node).textContent.trim();
            node = this._removeAndGetNext(node);
            continue;
          }

          if (shouldRemoveTitleHeader && this._headerDuplicatesTitle(node)) {
            this.log('Removing header: ', node.textContent.trim(), this._articleTitle.trim());
            shouldRemoveTitleHeader = false;
            node = this._removeAndGetNext(node);
            continue;
          }

          // Remove unlikely candidates
          if (stripUnlikelyCandidates) {
            if (
              this.REGEXPS.unlikelyCandidates.test(matchString) &&
              !this.REGEXPS.okMaybeItsACandidate.test(matchString) &&
              !this._hasAncestorTag(node, 'table') &&
              !this._hasAncestorTag(node, 'code') &&
              node.tagName !== 'BODY' &&
              node.tagName !== 'A'
            ) {
              this.log('Removing unlikely candidate - ' + matchString);
              node = this._removeAndGetNext(node);
              continue;
            }

            if (this.UNLIKELY_ROLES.includes(node.getAttribute('role'))) {
              this.log(
                'Removing content with role ' + node.getAttribute('role') + ' - ' + matchString,
              );
              node = this._removeAndGetNext(node);
              continue;
            }
          }

          // Remove DIV, SECTION, and HEADER nodes without any content(e.g. text, image, video, or iframe).
          if (
            (node.tagName === 'DIV' ||
              node.tagName === 'SECTION' ||
              node.tagName === 'HEADER' ||
              node.tagName === 'H1' ||
              node.tagName === 'H2' ||
              node.tagName === 'H3' ||
              node.tagName === 'H4' ||
              node.tagName === 'H5' ||
              node.tagName === 'H6') &&
            this._isElementWithoutContent(node)
          ) {
            node = this._removeAndGetNext(node);
            continue;
          }

          if (this.DEFAULT_TAGS_TO_SCORE.includes(node.tagName)) {
            elementsToScore.push(node);
          }

          // Turn all divs that don't have children block level elements into p's
          if (node.tagName === 'DIV') {
            // Put phrasing content into paragraphs.
            var p = null;
            var childNode = node.firstChild;
            while (childNode) {
              var nextSibling = childNode.nextSibling;
              if (this._isPhrasingContent(childNode)) {
                if (p !== null) {
                  p.appendChild(childNode);
                } else if (!this._isWhitespace(childNode)) {
                  p = doc.createElement('p');
                  node.replaceChild(p, childNode);
                  p.appendChild(childNode);
                }
              } else if (p !== null) {
                while (p.lastChild && this._isWhitespace(p.lastChild)) {
                  p.lastChild.remove();
                }
                p = null;
              }
              childNode = nextSibling;
            }

            // Sites like http://mobile.slate.com encloses each paragraph with a DIV
            // element. DIVs with only a P element inside and no text content can be
            // safely converted into plain P elements to avoid confusing the scoring
            // algorithm with DIVs with are, in practice, paragraphs.
            if (this._hasSingleTagInsideElement(node, 'P') && this._getLinkDensity(node) < 0.25) {
              var newNode = node.children[0];
              node.parentNode.replaceChild(newNode, node);
              node = newNode;
              elementsToScore.push(node);
            } else if (!this._hasChildBlockElement(node)) {
              node = this._setNodeTag(node, 'P');
              elementsToScore.push(node);
            }
          }
          node = this._getNextNode(node);
        }

        /**
         * Loop through all paragraphs, and assign a score to them based on how content-y they look.
         * Then add their score to their parent node.
         *
         * A score is determined by things like number of commas, class names, etc. Maybe eventually link density.
         **/
        var candidates = [];
        this._forEachNode(elementsToScore, function (elementToScore) {
          if (
            !elementToScore.parentNode ||
            typeof elementToScore.parentNode.tagName === 'undefined'
          ) {
            return;
          }

          // If this paragraph is less than 25 characters, don't even count it.
          var innerText = this._getInnerText(elementToScore);
          if (innerText.length < 25) {
            return;
          }

          // Exclude nodes with no ancestor.
          var ancestors = this._getNodeAncestors(elementToScore, 5);
          if (ancestors.length === 0) {
            return;
          }

          var contentScore = 0;

          // Add a point for the paragraph itself as a base.
          contentScore += 1;

          // Add points for any commas within this paragraph.
          contentScore += innerText.split(this.REGEXPS.commas).length;

          // For every 100 characters in this paragraph, add another point. Up to 3 points.
          contentScore += Math.min(Math.floor(innerText.length / 100), 3);

          // Initialize and score ancestors.
          this._forEachNode(ancestors, function (ancestor, level) {
            if (
              !ancestor.tagName ||
              !ancestor.parentNode ||
              typeof ancestor.parentNode.tagName === 'undefined'
            ) {
              return;
            }

            if (typeof ancestor.readability === 'undefined') {
              this._initializeNode(ancestor);
              candidates.push(ancestor);
            }

            // Node score divider:
            // - parent:             1 (no division)
            // - grandparent:        2
            // - great grandparent+: ancestor level * 3
            if (level === 0) {
              var scoreDivider = 1;
            } else if (level === 1) {
              scoreDivider = 2;
            } else {
              scoreDivider = level * 3;
            }
            ancestor.readability.contentScore += contentScore / scoreDivider;
          });
        });

        // After we've calculated scores, loop through all of the possible
        // candidate nodes we found and find the one with the highest score.
        var topCandidates = [];
        for (var c = 0, cl = candidates.length; c < cl; c += 1) {
          var candidate = candidates[c];

          // Scale the final candidates score based on link density. Good content
          // should have a relatively small link density (5% or less) and be mostly
          // unaffected by this operation.
          var candidateScore =
            candidate.readability.contentScore * (1 - this._getLinkDensity(candidate));
          candidate.readability.contentScore = candidateScore;

          this.log('Candidate:', candidate, 'with score ' + candidateScore);

          for (var t = 0; t < this._nbTopCandidates; t++) {
            var aTopCandidate = topCandidates[t];

            if (!aTopCandidate || candidateScore > aTopCandidate.readability.contentScore) {
              topCandidates.splice(t, 0, candidate);
              if (topCandidates.length > this._nbTopCandidates) {
                topCandidates.pop();
              }
              break;
            }
          }
        }

        var topCandidate = topCandidates[0] || null;
        var neededToCreateTopCandidate = false;
        var parentOfTopCandidate;

        // If we still have no top candidate, just use the body as a last resort.
        // We also have to copy the body node so it is something we can modify.
        if (topCandidate === null || topCandidate.tagName === 'BODY') {
          // Move all of the page's children into topCandidate
          topCandidate = doc.createElement('DIV');
          neededToCreateTopCandidate = true;
          // Move everything (not just elements, also text nodes etc.) into the container
          // so we even include text directly in the body:
          while (page.firstChild) {
            this.log('Moving child out:', page.firstChild);
            topCandidate.appendChild(page.firstChild);
          }

          page.appendChild(topCandidate);

          this._initializeNode(topCandidate);
        } else if (topCandidate) {
          // Find a better top candidate node if it contains (at least three) nodes which belong to `topCandidates` array
          // and whose scores are quite closed with current `topCandidate` node.
          var alternativeCandidateAncestors = [];
          for (var i = 1; i < topCandidates.length; i++) {
            if (
              topCandidates[i].readability.contentScore / topCandidate.readability.contentScore >=
              0.75
            ) {
              alternativeCandidateAncestors.push(this._getNodeAncestors(topCandidates[i]));
            }
          }
          var MINIMUM_TOPCANDIDATES = 3;
          if (alternativeCandidateAncestors.length >= MINIMUM_TOPCANDIDATES) {
            parentOfTopCandidate = topCandidate.parentNode;
            while (parentOfTopCandidate.tagName !== 'BODY') {
              var listsContainingThisAncestor = 0;
              for (
                var ancestorIndex = 0;
                ancestorIndex < alternativeCandidateAncestors.length &&
                listsContainingThisAncestor < MINIMUM_TOPCANDIDATES;
                ancestorIndex++
              ) {
                listsContainingThisAncestor += Number(
                  alternativeCandidateAncestors[ancestorIndex].includes(parentOfTopCandidate),
                );
              }
              if (listsContainingThisAncestor >= MINIMUM_TOPCANDIDATES) {
                topCandidate = parentOfTopCandidate;
                break;
              }
              parentOfTopCandidate = parentOfTopCandidate.parentNode;
            }
          }
          if (!topCandidate.readability) {
            this._initializeNode(topCandidate);
          }

          // Because of our bonus system, parents of candidates might have scores
          // themselves. They get half of the node. There won't be nodes with higher
          // scores than our topCandidate, but if we see the score going *up* in the first
          // few steps up the tree, that's a decent sign that there might be more content
          // lurking in other places that we want to unify in. The sibling stuff
          // below does some of that - but only if we've looked high enough up the DOM
          // tree.
          parentOfTopCandidate = topCandidate.parentNode;
          var lastScore = topCandidate.readability.contentScore;
          // The scores shouldn't get too low.
          var scoreThreshold = lastScore / 3;
          while (parentOfTopCandidate.tagName !== 'BODY') {
            if (!parentOfTopCandidate.readability) {
              parentOfTopCandidate = parentOfTopCandidate.parentNode;
              continue;
            }
            var parentScore = parentOfTopCandidate.readability.contentScore;
            if (parentScore < scoreThreshold) {
              break;
            }
            if (parentScore > lastScore) {
              // Alright! We found a better parent to use.
              topCandidate = parentOfTopCandidate;
              break;
            }
            lastScore = parentOfTopCandidate.readability.contentScore;
            parentOfTopCandidate = parentOfTopCandidate.parentNode;
          }

          // If the top candidate is the only child, use parent instead. This will help sibling
          // joining logic when adjacent content is actually located in parent's sibling node.
          parentOfTopCandidate = topCandidate.parentNode;
          while (
            parentOfTopCandidate.tagName != 'BODY' &&
            parentOfTopCandidate.children.length == 1
          ) {
            topCandidate = parentOfTopCandidate;
            parentOfTopCandidate = topCandidate.parentNode;
          }
          if (!topCandidate.readability) {
            this._initializeNode(topCandidate);
          }
        }

        // Now that we have the top candidate, look through its siblings for content
        // that might also be related. Things like preambles, content split by ads
        // that we removed, etc.
        var articleContent = doc.createElement('DIV');
        if (isPaging) {
          articleContent.id = 'readability-content';
        }

        var siblingScoreThreshold = Math.max(10, topCandidate.readability.contentScore * 0.2);
        // Keep potential top candidate's parent node to try to get text direction of it later.
        parentOfTopCandidate = topCandidate.parentNode;
        var siblings = parentOfTopCandidate.children;

        for (var s = 0, sl = siblings.length; s < sl; s++) {
          var sibling = siblings[s];
          var append = false;

          this.log(
            'Looking at sibling node:',
            sibling,
            sibling.readability ? 'with score ' + sibling.readability.contentScore : '',
          );
          this.log(
            'Sibling has score',
            sibling.readability ? sibling.readability.contentScore : 'Unknown',
          );

          if (sibling === topCandidate) {
            append = true;
          } else {
            var contentBonus = 0;

            // Give a bonus if sibling nodes and top candidates have the example same classname
            if (sibling.className === topCandidate.className && topCandidate.className !== '') {
              contentBonus += topCandidate.readability.contentScore * 0.2;
            }

            if (
              sibling.readability &&
              sibling.readability.contentScore + contentBonus >= siblingScoreThreshold
            ) {
              append = true;
            } else if (sibling.nodeName === 'P') {
              var linkDensity = this._getLinkDensity(sibling);
              var nodeContent = this._getInnerText(sibling);
              var nodeLength = nodeContent.length;

              if (nodeLength > 80 && linkDensity < 0.25) {
                append = true;
              } else if (
                nodeLength < 80 &&
                nodeLength > 0 &&
                linkDensity === 0 &&
                nodeContent.search(/\.( |$)/) !== -1
              ) {
                append = true;
              }
            }
          }

          if (append) {
            this.log('Appending node:', sibling);

            if (!this.ALTER_TO_DIV_EXCEPTIONS.includes(sibling.nodeName)) {
              // We have a node that isn't a common block level element, like a form or td tag.
              // Turn it into a div so it doesn't get filtered out later by accident.
              this.log('Altering sibling:', sibling, 'to div.');

              sibling = this._setNodeTag(sibling, 'DIV');
            }

            articleContent.appendChild(sibling);
            // Fetch children again to make it compatible
            // with DOM parsers without live collection support.
            siblings = parentOfTopCandidate.children;
            // siblings is a reference to the children array, and
            // sibling is removed from the array when we call appendChild().
            // As a result, we must revisit this index since the nodes
            // have been shifted.
            s -= 1;
            sl -= 1;
          }
        }

        if (this._debug) {
          this.log('Article content pre-prep: ' + articleContent.innerHTML);
        }
        // So we have all of the content that we need. Now we clean it up for presentation.
        this._prepArticle(articleContent);
        if (this._debug) {
          this.log('Article content post-prep: ' + articleContent.innerHTML);
        }

        if (neededToCreateTopCandidate) {
          // We already created a fake div thing, and there wouldn't have been any siblings left
          // for the previous loop, so there's no point trying to create a new div, and then
          // move all the children over. Just assign IDs and class names here. No need to append
          // because that already happened anyway.
          topCandidate.id = 'readability-page-1';
          topCandidate.className = 'page';
        } else {
          var div = doc.createElement('DIV');
          div.id = 'readability-page-1';
          div.className = 'page';
          while (articleContent.firstChild) {
            div.appendChild(articleContent.firstChild);
          }
          articleContent.appendChild(div);
        }

        if (this._debug) {
          this.log('Article content after paging: ' + articleContent.innerHTML);
        }

        var parseSuccessful = true;

        // Now that we've gone through the full algorithm, check to see if
        // we got any meaningful content. If we didn't, we may need to re-run
        // grabArticle with different flags set. This gives us a higher likelihood of
        // finding the content, and the sieve approach gives us a higher likelihood of
        // finding the -right- content.
        var textLength = this._getInnerText(articleContent, true).length;
        if (textLength < this._charThreshold) {
          parseSuccessful = false;
          // eslint-disable-next-line no-unsanitized/property
          page.innerHTML = pageCacheHtml;

          this._attempts.push({
            articleContent,
            textLength,
          });

          if (this._flagIsActive(this.FLAG_STRIP_UNLIKELYS)) {
            this._removeFlag(this.FLAG_STRIP_UNLIKELYS);
          } else if (this._flagIsActive(this.FLAG_WEIGHT_CLASSES)) {
            this._removeFlag(this.FLAG_WEIGHT_CLASSES);
          } else if (this._flagIsActive(this.FLAG_CLEAN_CONDITIONALLY)) {
            this._removeFlag(this.FLAG_CLEAN_CONDITIONALLY);
          } else {
            // No luck after removing flags, just return the longest text we found during the different loops
            this._attempts.sort(function (a, b) {
              return b.textLength - a.textLength;
            });

            // But first check if we actually have something
            if (!this._attempts[0].textLength) {
              return null;
            }

            articleContent = this._attempts[0].articleContent;
            parseSuccessful = true;
          }
        }

        if (parseSuccessful) {
          // Find out text direction from ancestors of final top candidate.
          var ancestors = [parentOfTopCandidate, topCandidate].concat(
            this._getNodeAncestors(parentOfTopCandidate),
          );
          this._someNode(ancestors, function (ancestor) {
            if (!ancestor.tagName) {
              return false;
            }
            var articleDir = ancestor.getAttribute('dir');
            if (articleDir) {
              this._articleDir = articleDir;
              return true;
            }
            return false;
          });
          return articleContent;
        }
      }
    },

    /**
     * Converts some of the common HTML entities in string to their corresponding characters.
     *
     * @param str {string} - a string to unescape.
     * @return string without HTML entity.
     */
    _unescapeHtmlEntities(str) {
      if (!str) {
        return str;
      }

      var htmlEscapeMap = this.HTML_ESCAPE_MAP;
      return str
        .replace(/&(quot|amp|apos|lt|gt);/g, function (_, tag) {
          return htmlEscapeMap[tag];
        })
        .replace(/&#(?:x([0-9a-f]+)|([0-9]+));/gi, function (_, hex, numStr) {
          var num = parseInt(hex || numStr, hex ? 16 : 10);

          // these character references are replaced by a conforming HTML parser
          if (num == 0 || num > 0x10ffff || (num >= 0xd800 && num <= 0xdfff)) {
            num = 0xfffd;
          }

          return String.fromCodePoint(num);
        });
    },

    /**
     * Try to extract metadata from JSON-LD object.
     * For now, only Schema.org objects of type Article or its subtypes are supported.
     * @return Object with any metadata that could be extracted (possibly none)
     */
    _getJSONLD(doc) {
      var scripts = this._getAllNodesWithTag(doc, ['script']);

      var metadata;

      this._forEachNode(scripts, function (jsonLdElement) {
        if (!metadata && jsonLdElement.getAttribute('type') === 'application/ld+json') {
          try {
            // Strip CDATA markers if present
            var content = jsonLdElement.textContent.replace(/^\s*<!\[CDATA\[|\]\]>\s*$/g, '');
            var parsed = JSON.parse(content);

            if (Array.isArray(parsed)) {
              parsed = parsed.find((it) => {
                return it['@type'] && it['@type'].match(this.REGEXPS.jsonLdArticleTypes);
              });
              if (!parsed) {
                return;
              }
            }

            var schemaDotOrgRegex = /^https?\:\/\/schema\.org\/?$/;
            var matches =
              (typeof parsed['@context'] === 'string' &&
                parsed['@context'].match(schemaDotOrgRegex)) ||
              (typeof parsed['@context'] === 'object' &&
                typeof parsed['@context']['@vocab'] == 'string' &&
                parsed['@context']['@vocab'].match(schemaDotOrgRegex));

            if (!matches) {
              return;
            }

            if (!parsed['@type'] && Array.isArray(parsed['@graph'])) {
              parsed = parsed['@graph'].find((it) => {
                return (it['@type'] || '').match(this.REGEXPS.jsonLdArticleTypes);
              });
            }

            if (
              !parsed ||
              !parsed['@type'] ||
              !parsed['@type'].match(this.REGEXPS.jsonLdArticleTypes)
            ) {
              return;
            }

            metadata = {};

            if (
              typeof parsed.name === 'string' &&
              typeof parsed.headline === 'string' &&
              parsed.name !== parsed.headline
            ) {
              // we have both name and headline element in the JSON-LD. They should both be the same but some websites like aktualne.cz
              // put their own name into "name" and the article title to "headline" which confuses Readability. So we try to check if either
              // "name" or "headline" closely matches the html title, and if so, use that one. If not, then we use "name" by default.

              var title = this._getArticleTitle();
              var nameMatches = this._textSimilarity(parsed.name, title) > 0.75;
              var headlineMatches = this._textSimilarity(parsed.headline, title) > 0.75;

              if (headlineMatches && !nameMatches) {
                metadata.title = parsed.headline;
              } else {
                metadata.title = parsed.name;
              }
            } else if (typeof parsed.name === 'string') {
              metadata.title = parsed.name.trim();
            } else if (typeof parsed.headline === 'string') {
              metadata.title = parsed.headline.trim();
            }
            if (parsed.author) {
              if (typeof parsed.author.name === 'string') {
                metadata.byline = parsed.author.name.trim();
              } else if (
                Array.isArray(parsed.author) &&
                parsed.author[0] &&
                typeof parsed.author[0].name === 'string'
              ) {
                metadata.byline = parsed.author
                  .filter(function (author) {
                    return author && typeof author.name === 'string';
                  })
                  .map(function (author) {
                    return author.name.trim();
                  })
                  .join(', ');
              }
            }
            if (typeof parsed.description === 'string') {
              metadata.excerpt = parsed.description.trim();
            }
            if (parsed.publisher && typeof parsed.publisher.name === 'string') {
              metadata.siteName = parsed.publisher.name.trim();
            }
            if (typeof parsed.datePublished === 'string') {
              metadata.datePublished = parsed.datePublished.trim();
            }
          } catch (err) {
            this.log(err.message);
          }
        }
      });
      return metadata ? metadata : {};
    },

    /**
     * Attempts to get excerpt and byline metadata for the article.
     *
     * @param {Object} jsonld — object containing any metadata that
     * could be extracted from JSON-LD object.
     *
     * @return Object with optional "excerpt" and "byline" properties
     */
    _getArticleMetadata(jsonld) {
      var metadata = {};
      var values = {};
      var metaElements = this._doc.getElementsByTagName('meta');

      // property is a space-separated list of values
      var propertyPattern =
        /\s*(article|dc|dcterm|og|twitter)\s*:\s*(author|creator|description|published_time|title|site_name)\s*/gi;

      // name is a single value
      var namePattern =
        /^\s*(?:(dc|dcterm|og|twitter|parsely|weibo:(article|webpage))\s*[-\.:]\s*)?(author|creator|pub-date|description|title|site_name)\s*$/i;

      // Find description tags.
      this._forEachNode(metaElements, function (element) {
        var elementName = element.getAttribute('name');
        var elementProperty = element.getAttribute('property');
        var content = element.getAttribute('content');
        if (!content) {
          return;
        }
        var matches = null;
        var name = null;

        if (elementProperty) {
          matches = elementProperty.match(propertyPattern);
          if (matches) {
            // Convert to lowercase, and remove any whitespace
            // so we can match below.
            name = matches[0].toLowerCase().replace(/\s/g, '');
            // multiple authors
            values[name] = content.trim();
          }
        }
        if (!matches && elementName && namePattern.test(elementName)) {
          name = elementName;
          if (content) {
            // Convert to lowercase, remove any whitespace, and convert dots
            // to colons so we can match below.
            name = name.toLowerCase().replace(/\s/g, '').replace(/\./g, ':');
            values[name] = content.trim();
          }
        }
      });

      // get title
      metadata.title =
        jsonld.title ||
        values['dc:title'] ||
        values['dcterm:title'] ||
        values['og:title'] ||
        values['weibo:article:title'] ||
        values['weibo:webpage:title'] ||
        values.title ||
        values['twitter:title'] ||
        values['parsely-title'];

      if (!metadata.title) {
        metadata.title = this._getArticleTitle();
      }

      const articleAuthor =
        typeof values['article:author'] === 'string' && !this._isUrl(values['article:author'])
          ? values['article:author']
          : undefined;

      // get author
      metadata.byline =
        jsonld.byline ||
        values['dc:creator'] ||
        values['dcterm:creator'] ||
        values.author ||
        values['parsely-author'] ||
        articleAuthor;

      // get description
      metadata.excerpt =
        jsonld.excerpt ||
        values['dc:description'] ||
        values['dcterm:description'] ||
        values['og:description'] ||
        values['weibo:article:description'] ||
        values['weibo:webpage:description'] ||
        values.description ||
        values['twitter:description'];

      // get site name
      metadata.siteName = jsonld.siteName || values['og:site_name'];

      // get article published time
      metadata.publishedTime =
        jsonld.datePublished ||
        values['article:published_time'] ||
        values['parsely-pub-date'] ||
        null;

      // in many sites the meta value is escaped with HTML entities,
      // so here we need to unescape it
      metadata.title = this._unescapeHtmlEntities(metadata.title);
      metadata.byline = this._unescapeHtmlEntities(metadata.byline);
      metadata.excerpt = this._unescapeHtmlEntities(metadata.excerpt);
      metadata.siteName = this._unescapeHtmlEntities(metadata.siteName);
      metadata.publishedTime = this._unescapeHtmlEntities(metadata.publishedTime);

      return metadata;
    },

    /**
     * Check if node is image, or if node contains exactly only one image
     * whether as a direct child or as its descendants.
     *
     * @param Element
     **/
    _isSingleImage(node) {
      while (node) {
        if (node.tagName === 'IMG') {
          return true;
        }
        if (node.children.length !== 1 || node.textContent.trim() !== '') {
          return false;
        }
        node = node.children[0];
      }
      return false;
    },

    /**
     * Find all <noscript> that are located after <img> nodes, and which contain only one
     * <img> element. Replace the first image with the image from inside the <noscript> tag,
     * and remove the <noscript> tag. This improves the quality of the images we use on
     * some sites (e.g. Medium).
     *
     * @param Element
     **/
    _unwrapNoscriptImages(doc) {
      // Find img without source or attributes that might contains image, and remove it.
      // This is done to prevent a placeholder img is replaced by img from noscript in next step.
      var imgs = Array.from(doc.getElementsByTagName('img'));
      this._forEachNode(imgs, function (img) {
        for (var i = 0; i < img.attributes.length; i++) {
          var attr = img.attributes[i];
          switch (attr.name) {
            case 'src':
            case 'srcset':
            case 'data-src':
            case 'data-srcset':
              return;
          }

          if (/\.(jpg|jpeg|png|webp)/i.test(attr.value)) {
            return;
          }
        }

        img.remove();
      });

      // Next find noscript and try to extract its image
      var noscripts = Array.from(doc.getElementsByTagName('noscript'));
      this._forEachNode(noscripts, function (noscript) {
        // Parse content of noscript and make sure it only contains image
        if (!this._isSingleImage(noscript)) {
          return;
        }
        var tmp = doc.createElement('div');
        // We're running in the document context, and using unmodified
        // document contents, so doing this should be safe.
        // (Also we heavily discourage people from allowing script to
        // run at all in this document...)
        // eslint-disable-next-line no-unsanitized/property
        tmp.innerHTML = noscript.innerHTML;

        // If noscript has previous sibling and it only contains image,
        // replace it with noscript content. However we also keep old
        // attributes that might contains image.
        var prevElement = noscript.previousElementSibling;
        if (prevElement && this._isSingleImage(prevElement)) {
          var prevImg = prevElement;
          if (prevImg.tagName !== 'IMG') {
            prevImg = prevElement.getElementsByTagName('img')[0];
          }

          var newImg = tmp.getElementsByTagName('img')[0];
          for (var i = 0; i < prevImg.attributes.length; i++) {
            var attr = prevImg.attributes[i];
            if (attr.value === '') {
              continue;
            }

            if (
              attr.name === 'src' ||
              attr.name === 'srcset' ||
              /\.(jpg|jpeg|png|webp)/i.test(attr.value)
            ) {
              if (newImg.getAttribute(attr.name) === attr.value) {
                continue;
              }

              var attrName = attr.name;
              if (newImg.hasAttribute(attrName)) {
                attrName = 'data-old-' + attrName;
              }

              newImg.setAttribute(attrName, attr.value);
            }
          }

          noscript.parentNode.replaceChild(tmp.firstElementChild, prevElement);
        }
      });
    },

    /**
     * Removes script tags from the document.
     *
     * @param Element
     **/
    _removeScripts(doc) {
      this._removeNodes(this._getAllNodesWithTag(doc, ['script', 'noscript']));
    },

    /**
     * Check if this node has only whitespace and a single element with given tag
     * Returns false if the DIV node contains non-empty text nodes
     * or if it contains no element with given tag or more than 1 element.
     *
     * @param Element
     * @param string tag of child element
     **/
    _hasSingleTagInsideElement(element, tag) {
      // There should be exactly 1 element child with given tag
      if (element.children.length != 1 || element.children[0].tagName !== tag) {
        return false;
      }

      // And there should be no text nodes with real content
      return !this._someNode(element.childNodes, function (node) {
        return node.nodeType === this.TEXT_NODE && this.REGEXPS.hasContent.test(node.textContent);
      });
    },

    _isElementWithoutContent(node) {
      return (
        node.nodeType === this.ELEMENT_NODE &&
        !node.textContent.trim().length &&
        (!node.children.length ||
          node.children.length ==
            node.getElementsByTagName('br').length + node.getElementsByTagName('hr').length)
      );
    },

    /**
     * Determine whether element has any children block level elements.
     *
     * @param Element
     */
    _hasChildBlockElement(element) {
      return this._someNode(element.childNodes, function (node) {
        return this.DIV_TO_P_ELEMS.has(node.tagName) || this._hasChildBlockElement(node);
      });
    },

    /***
     * Determine if a node qualifies as phrasing content.
     * https://developer.mozilla.org/en-US/docs/Web/Guide/HTML/Content_categories#Phrasing_content
     **/
    _isPhrasingContent(node) {
      return (
        node.nodeType === this.TEXT_NODE ||
        this.PHRASING_ELEMS.includes(node.tagName) ||
        ((node.tagName === 'A' || node.tagName === 'DEL' || node.tagName === 'INS') &&
          this._everyNode(node.childNodes, this._isPhrasingContent))
      );
    },

    _isWhitespace(node) {
      return (
        (node.nodeType === this.TEXT_NODE && node.textContent.trim().length === 0) ||
        (node.nodeType === this.ELEMENT_NODE && node.tagName === 'BR')
      );
    },

    /**
     * Get the inner text of a node - cross browser compatibly.
     * This also strips out any excess whitespace to be found.
     *
     * @param Element
     * @param Boolean normalizeSpaces (default: true)
     * @return string
     **/
    _getInnerText(e, normalizeSpaces) {
      normalizeSpaces = typeof normalizeSpaces === 'undefined' ? true : normalizeSpaces;
      var textContent = e.textContent.trim();

      if (normalizeSpaces) {
        return textContent.replace(this.REGEXPS.normalize, ' ');
      }
      return textContent;
    },

    /**
     * Get the number of times a string s appears in the node e.
     *
     * @param Element
     * @param string - what to split on. Default is ","
     * @return number (integer)
     **/
    _getCharCount(e, s) {
      s = s || ',';
      return this._getInnerText(e).split(s).length - 1;
    },

    /**
     * Remove the style attribute on every e and under.
     * TODO: Test if getElementsByTagName(*) is faster.
     *
     * @param Element
     * @return void
     **/
    _cleanStyles(e) {
      if (!e || e.tagName.toLowerCase() === 'svg') {
        return;
      }

      // Remove `style` and deprecated presentational attributes
      for (var i = 0; i < this.PRESENTATIONAL_ATTRIBUTES.length; i++) {
        e.removeAttribute(this.PRESENTATIONAL_ATTRIBUTES[i]);
      }

      if (this.DEPRECATED_SIZE_ATTRIBUTE_ELEMS.includes(e.tagName)) {
        e.removeAttribute('width');
        e.removeAttribute('height');
      }

      var cur = e.firstElementChild;
      while (cur !== null) {
        this._cleanStyles(cur);
        cur = cur.nextElementSibling;
      }
    },

    /**
     * Get the density of links as a percentage of the content
     * This is the amount of text that is inside a link divided by the total text in the node.
     *
     * @param Element
     * @return number (float)
     **/
    _getLinkDensity(element) {
      var textLength = this._getInnerText(element).length;
      if (textLength === 0) {
        return 0;
      }

      var linkLength = 0;

      // XXX implement _reduceNodeList?
      this._forEachNode(element.getElementsByTagName('a'), function (linkNode) {
        var href = linkNode.getAttribute('href');
        var coefficient = href && this.REGEXPS.hashUrl.test(href) ? 0.3 : 1;
        linkLength += this._getInnerText(linkNode).length * coefficient;
      });

      return linkLength / textLength;
    },

    /**
     * Get an elements class/id weight. Uses regular expressions to tell if this
     * element looks good or bad.
     *
     * @param Element
     * @return number (Integer)
     **/
    _getClassWeight(e) {
      if (!this._flagIsActive(this.FLAG_WEIGHT_CLASSES)) {
        return 0;
      }

      var weight = 0;

      // Look for a special classname
      if (typeof e.className === 'string' && e.className !== '') {
        if (this.REGEXPS.negative.test(e.className)) {
          weight -= 25;
        }

        if (this.REGEXPS.positive.test(e.className)) {
          weight += 25;
        }
      }

      // Look for a special ID
      if (typeof e.id === 'string' && e.id !== '') {
        if (this.REGEXPS.negative.test(e.id)) {
          weight -= 25;
        }

        if (this.REGEXPS.positive.test(e.id)) {
          weight += 25;
        }
      }

      return weight;
    },

    /**
     * Clean a node of all elements of type "tag".
     * (Unless it's a youtube/vimeo video. People love movies.)
     *
     * @param Element
     * @param string tag to clean
     * @return void
     **/
    _clean(e, tag) {
      var isEmbed = ['object', 'embed', 'iframe'].includes(tag);

      this._removeNodes(this._getAllNodesWithTag(e, [tag]), function (element) {
        // Allow youtube and vimeo videos through as people usually want to see those.
        if (isEmbed) {
          // First, check the elements attributes to see if any of them contain youtube or vimeo
          for (var i = 0; i < element.attributes.length; i++) {
            if (this._allowedVideoRegex.test(element.attributes[i].value)) {
              return false;
            }
          }

          // For embed with <object> tag, check inner HTML as well.
          if (element.tagName === 'object' && this._allowedVideoRegex.test(element.innerHTML)) {
            return false;
          }
        }

        return true;
      });
    },

    /**
     * Check if a given node has one of its ancestor tag name matching the
     * provided one.
     * @param  HTMLElement node
     * @param  String      tagName
     * @param  Number      maxDepth
     * @param  Function    filterFn a filter to invoke to determine whether this node 'counts'
     * @return Boolean
     */
    _hasAncestorTag(node, tagName, maxDepth, filterFn) {
      maxDepth = maxDepth || 3;
      tagName = tagName.toUpperCase();
      var depth = 0;
      while (node.parentNode) {
        if (maxDepth > 0 && depth > maxDepth) {
          return false;
        }
        if (node.parentNode.tagName === tagName && (!filterFn || filterFn(node.parentNode))) {
          return true;
        }
        node = node.parentNode;
        depth++;
      }
      return false;
    },

    /**
     * Return an object indicating how many rows and columns this table has.
     */
    _getRowAndColumnCount(table) {
      var rows = 0;
      var columns = 0;
      var trs = table.getElementsByTagName('tr');
      for (var i = 0; i < trs.length; i++) {
        var rowspan = trs[i].getAttribute('rowspan') || 0;
        if (rowspan) {
          rowspan = parseInt(rowspan, 10);
        }
        rows += rowspan || 1;

        // Now look for column-related info
        var columnsInThisRow = 0;
        var cells = trs[i].getElementsByTagName('td');
        for (var j = 0; j < cells.length; j++) {
          var colspan = cells[j].getAttribute('colspan') || 0;
          if (colspan) {
            colspan = parseInt(colspan, 10);
          }
          columnsInThisRow += colspan || 1;
        }
        columns = Math.max(columns, columnsInThisRow);
      }
      return { rows, columns };
    },

    /**
     * Look for 'data' (as opposed to 'layout') tables, for which we use
     * similar checks as
     * https://searchfox.org/mozilla-central/rev/f82d5c549f046cb64ce5602bfd894b7ae807c8f8/accessible/generic/TableAccessible.cpp#19
     */
    _markDataTables(root) {
      var tables = root.getElementsByTagName('table');
      for (var i = 0; i < tables.length; i++) {
        var table = tables[i];
        var role = table.getAttribute('role');
        if (role == 'presentation') {
          table._readabilityDataTable = false;
          continue;
        }
        var datatable = table.getAttribute('datatable');
        if (datatable == '0') {
          table._readabilityDataTable = false;
          continue;
        }
        var summary = table.getAttribute('summary');
        if (summary) {
          table._readabilityDataTable = true;
          continue;
        }

        var caption = table.getElementsByTagName('caption')[0];
        if (caption && caption.childNodes.length) {
          table._readabilityDataTable = true;
          continue;
        }

        // If the table has a descendant with any of these tags, consider a data table:
        var dataTableDescendants = ['col', 'colgroup', 'tfoot', 'thead', 'th'];
        var descendantExists = function (tag) {
          return !!table.getElementsByTagName(tag)[0];
        };
        if (dataTableDescendants.some(descendantExists)) {
          this.log('Data table because found data-y descendant');
          table._readabilityDataTable = true;
          continue;
        }

        // Nested tables indicate a layout table:
        if (table.getElementsByTagName('table')[0]) {
          table._readabilityDataTable = false;
          continue;
        }

        var sizeInfo = this._getRowAndColumnCount(table);

        if (sizeInfo.columns == 1 || sizeInfo.rows == 1) {
          // single colum/row tables are commonly used for page layout purposes.
          table._readabilityDataTable = false;
          continue;
        }

        if (sizeInfo.rows >= 10 || sizeInfo.columns > 4) {
          table._readabilityDataTable = true;
          continue;
        }
        // Now just go by size entirely:
        table._readabilityDataTable = sizeInfo.rows * sizeInfo.columns > 10;
      }
    },

    /* convert images and figures that have properties like data-src into images that can be loaded without JS */
    _fixLazyImages(root) {
      this._forEachNode(
        this._getAllNodesWithTag(root, ['img', 'picture', 'figure']),
        function (elem) {
          // In some sites (e.g. Kotaku), they put 1px square image as base64 data uri in the src attribute.
          // So, here we check if the data uri is too short, just might as well remove it.
          if (elem.src && this.REGEXPS.b64DataUrl.test(elem.src)) {
            // Make sure it's not SVG, because SVG can have a meaningful image in under 133 bytes.
            var parts = this.REGEXPS.b64DataUrl.exec(elem.src);
            if (parts[1] === 'image/svg+xml') {
              return;
            }

            // Make sure this element has other attributes which contains image.
            // If it doesn't, then this src is important and shouldn't be removed.
            var srcCouldBeRemoved = false;
            for (var i = 0; i < elem.attributes.length; i++) {
              var attr = elem.attributes[i];
              if (attr.name === 'src') {
                continue;
              }

              if (/\.(jpg|jpeg|png|webp)/i.test(attr.value)) {
                srcCouldBeRemoved = true;
                break;
              }
            }

            // Here we assume if image is less than 100 bytes (or 133 after encoded to base64)
            // it will be too small, therefore it might be placeholder image.
            if (srcCouldBeRemoved) {
              var b64starts = parts[0].length;
              var b64length = elem.src.length - b64starts;
              if (b64length < 133) {
                elem.removeAttribute('src');
              }
            }
          }

          // also check for "null" to work around https://github.com/jsdom/jsdom/issues/2580
          if (
            (elem.src || (elem.srcset && elem.srcset != 'null')) &&
            !elem.className.toLowerCase().includes('lazy')
          ) {
            return;
          }

          for (var j = 0; j < elem.attributes.length; j++) {
            attr = elem.attributes[j];
            if (attr.name === 'src' || attr.name === 'srcset' || attr.name === 'alt') {
              continue;
            }
            var copyTo = null;
            if (/\.(jpg|jpeg|png|webp)\s+\d/.test(attr.value)) {
              copyTo = 'srcset';
            } else if (/^\s*\S+\.(jpg|jpeg|png|webp)\S*\s*$/.test(attr.value)) {
              copyTo = 'src';
            }
            if (copyTo) {
              //if this is an img or picture, set the attribute directly
              if (elem.tagName === 'IMG' || elem.tagName === 'PICTURE') {
                elem.setAttribute(copyTo, attr.value);
              } else if (
                elem.tagName === 'FIGURE' &&
                !this._getAllNodesWithTag(elem, ['img', 'picture']).length
              ) {
                //if the item is a <figure> that does not contain an image or picture, create one and place it inside the figure
                //see the nytimes-3 testcase for an example
                var img = this._doc.createElement('img');
                img.setAttribute(copyTo, attr.value);
                elem.appendChild(img);
              }
            }
          }
        },
      );
    },

    _getTextDensity(e, tags) {
      var textLength = this._getInnerText(e, true).length;
      if (textLength === 0) {
        return 0;
      }
      var childrenLength = 0;
      var children = this._getAllNodesWithTag(e, tags);
      this._forEachNode(
        children,
        (child) => (childrenLength += this._getInnerText(child, true).length),
      );
      return childrenLength / textLength;
    },

    /**
     * Clean an element of all tags of type "tag" if they look fishy.
     * "Fishy" is an algorithm based on content length, classnames, link density, number of images & embeds, etc.
     *
     * @return void
     **/
    _cleanConditionally(e, tag) {
      if (!this._flagIsActive(this.FLAG_CLEAN_CONDITIONALLY)) {
        return;
      }

      // Gather counts for other typical elements embedded within.
      // Traverse backwards so we can remove nodes at the same time
      // without effecting the traversal.
      //
      // TODO: Consider taking into account original contentScore here.
      this._removeNodes(this._getAllNodesWithTag(e, [tag]), function (node) {
        // First check if this node IS data table, in which case don't remove it.
        var isDataTable = function (t) {
          return t._readabilityDataTable;
        };

        var isList = tag === 'ul' || tag === 'ol';
        if (!isList) {
          var listLength = 0;
          var listNodes = this._getAllNodesWithTag(node, ['ul', 'ol']);
          this._forEachNode(listNodes, (list) => (listLength += this._getInnerText(list).length));
          isList = listLength / this._getInnerText(node).length > 0.9;
        }

        if (tag === 'table' && isDataTable(node)) {
          return false;
        }

        // Next check if we're inside a data table, in which case don't remove it as well.
        if (this._hasAncestorTag(node, 'table', -1, isDataTable)) {
          return false;
        }

        if (this._hasAncestorTag(node, 'code')) {
          return false;
        }

        // keep element if it has a data tables
        if ([...node.getElementsByTagName('table')].some((tbl) => tbl._readabilityDataTable)) {
          return false;
        }

        var weight = this._getClassWeight(node);

        this.log('Cleaning Conditionally', node);

        var contentScore = 0;

        if (weight + contentScore < 0) {
          return true;
        }

        if (this._getCharCount(node, ',') < 10) {
          // If there are not very many commas, and the number of
          // non-paragraph elements is more than paragraphs or other
          // ominous signs, remove the element.
          var p = node.getElementsByTagName('p').length;
          var img = node.getElementsByTagName('img').length;
          var li = node.getElementsByTagName('li').length - 100;
          var input = node.getElementsByTagName('input').length;
          var headingDensity = this._getTextDensity(node, ['h1', 'h2', 'h3', 'h4', 'h5', 'h6']);

          var embedCount = 0;
          var embeds = this._getAllNodesWithTag(node, ['object', 'embed', 'iframe']);

          for (var i = 0; i < embeds.length; i++) {
            // If this embed has attribute that matches video regex, don't delete it.
            for (var j = 0; j < embeds[i].attributes.length; j++) {
              if (this._allowedVideoRegex.test(embeds[i].attributes[j].value)) {
                return false;
              }
            }

            // For embed with <object> tag, check inner HTML as well.
            if (
              embeds[i].tagName === 'object' &&
              this._allowedVideoRegex.test(embeds[i].innerHTML)
            ) {
              return false;
            }

            embedCount++;
          }

          var innerText = this._getInnerText(node);

          // toss any node whose inner text contains nothing but suspicious words
          if (this.REGEXPS.adWords.test(innerText) || this.REGEXPS.loadingWords.test(innerText)) {
            return true;
          }

          var contentLength = innerText.length;
          var linkDensity = this._getLinkDensity(node);
          var textishTags = ['SPAN', 'LI', 'TD'].concat(Array.from(this.DIV_TO_P_ELEMS));
          var textDensity = this._getTextDensity(node, textishTags);
          var isFigureChild = this._hasAncestorTag(node, 'figure');

          // apply shadiness checks, then check for exceptions
          const shouldRemoveNode = () => {
            const errs = [];
            if (!isFigureChild && img > 1 && p / img < 0.5) {
              errs.push(`Bad p to img ratio (img=${img}, p=${p})`);
            }
            if (!isList && li > p) {
              errs.push(`Too many li's outside of a list. (li=${li} > p=${p})`);
            }
            if (input > Math.floor(p / 3)) {
              errs.push(`Too many inputs per p. (input=${input}, p=${p})`);
            }
            if (
              !isList &&
              !isFigureChild &&
              headingDensity < 0.9 &&
              contentLength < 25 &&
              (img === 0 || img > 2) &&
              linkDensity > 0
            ) {
              errs.push(
                `Suspiciously short. (headingDensity=${headingDensity}, img=${img}, linkDensity=${linkDensity})`,
              );
            }
            if (!isList && weight < 25 && linkDensity > 0.2 + this._linkDensityModifier) {
              errs.push(`Low weight and a little linky. (linkDensity=${linkDensity})`);
            }
            if (weight >= 25 && linkDensity > 0.5 + this._linkDensityModifier) {
              errs.push(`High weight and mostly links. (linkDensity=${linkDensity})`);
            }
            if ((embedCount === 1 && contentLength < 75) || embedCount > 1) {
              errs.push(
                `Suspicious embed. (embedCount=${embedCount}, contentLength=${contentLength})`,
              );
            }
            if (img === 0 && textDensity === 0) {
              errs.push(`No useful content. (img=${img}, textDensity=${textDensity})`);
            }

            if (errs.length) {
              this.log('Checks failed', errs);
              return true;
            }

            return false;
          };

          var haveToRemove = shouldRemoveNode();

          // Allow simple lists of images to remain in pages
          if (isList && haveToRemove) {
            for (var x = 0; x < node.children.length; x++) {
              let child = node.children[x];
              // Don't filter in lists with li's that contain more than one child
              if (child.children.length > 1) {
                return haveToRemove;
              }
            }
            let li_count = node.getElementsByTagName('li').length;
            // Only allow the list to remain if every li contains an image
            if (img == li_count) {
              return false;
            }
          }
          return haveToRemove;
        }
        return false;
      });
    },

    /**
     * Clean out elements that match the specified conditions
     *
     * @param Element
     * @param Function determines whether a node should be removed
     * @return void
     **/
    _cleanMatchedNodes(e, filter) {
      var endOfSearchMarkerNode = this._getNextNode(e, true);
      var next = this._getNextNode(e);
      while (next && next != endOfSearchMarkerNode) {
        if (filter.call(this, next, next.className + ' ' + next.id)) {
          next = this._removeAndGetNext(next);
        } else {
          next = this._getNextNode(next);
        }
      }
    },

    /**
     * Clean out spurious headers from an Element.
     *
     * @param Element
     * @return void
     **/
    _cleanHeaders(e) {
      let headingNodes = this._getAllNodesWithTag(e, ['h1', 'h2']);
      this._removeNodes(headingNodes, function (node) {
        let shouldRemove = this._getClassWeight(node) < 0;
        if (shouldRemove) {
          this.log('Removing header with low class weight:', node);
        }
        return shouldRemove;
      });
    },

    /**
     * Check if this node is an H1 or H2 element whose content is mostly
     * the same as the article title.
     *
     * @param Element  the node to check.
     * @return boolean indicating whether this is a title-like header.
     */
    _headerDuplicatesTitle(node) {
      if (node.tagName != 'H1' && node.tagName != 'H2') {
        return false;
      }
      var heading = this._getInnerText(node, false);
      this.log('Evaluating similarity of header:', heading, this._articleTitle);
      return this._textSimilarity(this._articleTitle, heading) > 0.75;
    },

    _flagIsActive(flag) {
      return (this._flags & flag) > 0;
    },

    _removeFlag(flag) {
      this._flags = this._flags & ~flag;
    },

    _isProbablyVisible(node) {
      // Have to null-check node.style and node.className.includes to deal with SVG and MathML nodes.
      return (
        (!node.style || node.style.display != 'none') &&
        (!node.style || node.style.visibility != 'hidden') &&
        !node.hasAttribute('hidden') &&
        //check for "fallback-image" so that wikimedia math images are displayed
        (!node.hasAttribute('aria-hidden') ||
          node.getAttribute('aria-hidden') != 'true' ||
          (node.className && node.className.includes && node.className.includes('fallback-image')))
      );
    },

    /**
     * Runs readability.
     *
     * Workflow:
     *  1. Prep the document by removing script tags, css, etc.
     *  2. Build readability's DOM tree.
     *  3. Grab the article content from the current dom tree.
     *  4. Replace the current DOM tree with the new one.
     *  5. Read peacefully.
     *
     * @return void
     **/
    parse() {
      // Avoid parsing too large documents, as per configuration option
      if (this._maxElemsToParse > 0) {
        var numTags = this._doc.getElementsByTagName('*').length;
        if (numTags > this._maxElemsToParse) {
          throw new Error('Aborting parsing document; ' + numTags + ' elements found');
        }
      }

      // Unwrap image from noscript
      this._unwrapNoscriptImages(this._doc);

      // Extract JSON-LD metadata before removing scripts
      var jsonLd = this._disableJSONLD ? {} : this._getJSONLD(this._doc);

      // Remove script tags from the document.
      this._removeScripts(this._doc);

      this._prepDocument();

      var metadata = this._getArticleMetadata(jsonLd);
      this._metadata = metadata;
      this._articleTitle = metadata.title;

      var articleContent = this._grabArticle();
      if (!articleContent) {
        return null;
      }

      this.log('Grabbed: ' + articleContent.innerHTML);

      this._postProcessContent(articleContent);

      // If we haven't found an excerpt in the article's metadata, use the article's
      // first paragraph as the excerpt. This is used for displaying a preview of
      // the article's content.
      if (!metadata.excerpt) {
        var paragraphs = articleContent.getElementsByTagName('p');
        if (paragraphs.length) {
          metadata.excerpt = paragraphs[0].textContent.trim();
        }
      }

      var textContent = articleContent.textContent;
      return {
        title: this._articleTitle,
        byline: metadata.byline || this._articleByline,
        dir: this._articleDir,
        lang: this._articleLang,
        content: this._serializer(articleContent),
        textContent,
        length: textContent.length,
        excerpt: metadata.excerpt,
        siteName: metadata.siteName || this._articleSiteName,
        publishedTime: metadata.publishedTime,
      };
    },
  };

  if (typeof module === 'object') {
    /* global module */
    module.exports = Readability;
  }

  /**
   * Web Fetcher Helper Content Script
   * Handles fetching HTML content, text content, and interactive elements from the current page
   * Supports Readability for better content extraction
   */

  // Configuration
  const config = {
    // Elements that should be ignored when extracting content (used for iframe content and fallback extraction)
    ignoreElements: [
      'nav',
      'header:not(article header)',
      'footer:not(article footer)',
      'aside',
      'script',
      'style',
      'noscript',
      'iframe[src*="ads"]',
      '.cookie-notice',
      '.ad',
      '.ads',
      '.advertisement',
      '.banner',
      '.popup',
      '.modal',
      '.overlay',
      '.social-share',
      '.social-links',
      '.related-articles',
      '.comments',
    ],
    minTextLength: 20,
    maxTotalLength: 100000,
    minParagraphLength: 2,
  };

  // Listen for messages from the extension
  chrome.runtime.onMessage.addListener((request, _sender, sendResponse) => {
    const pingActions = ['search_tabs_content_ping', 'chrome_web_fetcher_ping'];
    // Respond to ping message
    if (pingActions.includes(request.action)) {
      sendResponse({ status: 'pong' });
      return false; // Synchronous response
    }

    // Get HTML content
    else if (request.action === 'getHtmlContent') {
      try {
        let rawHtml;

        // If selector is specified, only get content from the matching element
        if (request.selector) {
          const element = document.querySelector(request.selector);
          if (element) {
            rawHtml = element.outerHTML;
          } else {
            throw new Error(`No element found matching selector: ${request.selector}`);
          }
        } else {
          // Otherwise get the entire page content
          rawHtml = document.documentElement.outerHTML;
        }

        const cleanedHtml = cleanHtmlContent(rawHtml);

        sendResponse({
          success: true,
          htmlContent: cleanedHtml,
          selector: request.selector,
        });
      } catch (error) {
        sendResponse({
          success: false,
          error: `Failed to get HTML content: ${error.message}`,
        });
      }
    }

    // Get text content
    else if (request.action === 'getTextContent') {
      try {
        // If selector is specified, only get content from the matching element
        if (request.selector) {
          const element = document.querySelector(request.selector);
          if (element) {
            // Directly get the text content of the element
            const textContent = element.innerText;

            sendResponse({
              success: true,
              textContent: textContent,
              selector: request.selector,
            });
          } else {
            throw new Error(`No element found matching selector: ${request.selector}`);
          }
        } else {
          // Otherwise use Readability to extract the main content
          const documentClone = document.cloneNode(true);

          const reader = new Readability(documentClone);
          const article = reader.parse();

          if (article && article.textContent) {
            // Get metadata
            const metadata = extractPageMetadata();

            // Get iframe content if available
            const iframeContent = extractIframeContent();

            // Combine content
            let fullContent = article.textContent;
            if (iframeContent && iframeContent.trim().length > config.minTextLength) {
              fullContent += '\n\n--- Embedded Content ---\n\n' + iframeContent;
            }

            // Clean content
            fullContent = cleanContent(fullContent);

            sendResponse({
              success: true,
              textContent: fullContent,
              article: {
                title: article.title,
                byline: article.byline,
                siteName: article.siteName,
                excerpt: article.excerpt,
                lang: article.lang,
                content: article.content, // HTML content
              },
              metadata: metadata,
            });
          } else {
            // Fallback to basic extraction
            const textContent = document.body.innerText;
            sendResponse({
              success: true,
              textContent: textContent,
              fallback: true,
            });
          }
        }
      } catch (error) {
        console.error('Error extracting text content:', error);
        sendResponse({
          success: false,
          error: `Failed to extract text content: ${error.message}`,
        });
      }

      return true; // Async response
    }

    // Interactive elements feature has been removed

    return true; // Async response
  });

  /**
   * Extract metadata from the page
   * @returns {Object} - Page metadata
   */
  function extractPageMetadata() {
    const metadata = {
      title: document.title,
      description: '',
      author: '',
      keywords: '',
      published: '',
      siteName: '',
    };

    // Extract description
    const descriptionElement = document.querySelector(
      'meta[name="description"], meta[property="og:description"]',
    );
    if (descriptionElement) {
      metadata.description = descriptionElement.getAttribute('content') || '';
    }

    // Extract author
    const authorElement = document.querySelector(
      'meta[name="author"], meta[property="article:author"]',
    );
    if (authorElement) {
      metadata.author = authorElement.getAttribute('content') || '';
    }

    // Extract keywords
    const keywordsElement = document.querySelector('meta[name="keywords"]');
    if (keywordsElement) {
      metadata.keywords = keywordsElement.getAttribute('content') || '';
    }

    // Extract published date
    const publishedElement = document.querySelector(
      'meta[property="article:published_time"], time[datetime]',
    );
    if (publishedElement) {
      metadata.published =
        publishedElement.getAttribute('content') || publishedElement.getAttribute('datetime') || '';
    }

    // Extract site name
    const siteNameElement = document.querySelector('meta[property="og:site_name"]');
    if (siteNameElement) {
      metadata.siteName = siteNameElement.getAttribute('content') || '';
    }

    return metadata;
  }

  /**
   * Extract content from iframes
   * @returns {string} - Combined iframe content
   */
  function extractIframeContent() {
    let allIframeText = '';
    const iframes = document.querySelectorAll('iframe');

    for (const iframe of iframes) {
      try {
        if (isSameOrigin(iframe) && isElementVisible(iframe)) {
          const doc = iframe.contentDocument || iframe.contentWindow?.document;
          if (doc) {
            const iframeText = doc.body.innerText;
            if (iframeText && iframeText.trim().length >= config.minTextLength) {
              allIframeText += iframeText.trim() + '\n\n';
            }
          }
        }
      } catch (error) {
        console.warn(
          `Cannot access iframe content (possible cross-origin restriction): ${error.message}`,
        );
      }
    }

    return allIframeText.trim();
  }

  /**
   * Check if iframe is same origin
   * @param {HTMLIFrameElement} iframe - The iframe to check
   * @returns {boolean} - Whether the iframe is same origin
   */
  function isSameOrigin(iframe) {
    try {
      return Boolean(iframe.contentDocument || iframe.contentWindow?.document);
    } catch (e) {
      return false;
    }
  }

  /**
   * Clean content text
   * @param {string} text - The text to clean
   * @returns {string} - Cleaned text
   */
  function cleanContent(text) {
    return text
      .replace(/\s+/g, ' ')
      .replace(/\n\s*\n/g, '\n\n')
      .trim()
      .substring(0, config.maxTotalLength);
  }

  /**
   * Clean HTML content by removing style tags and their content
   * @param {string} html - The HTML content to clean
   * @returns {string} - Cleaned HTML content
   */
  function cleanHtmlContent(html) {
    // Create a new document parser
    const parser = new DOMParser();
    const doc = parser.parseFromString(html, 'text/html');

    // Remove all style tags
    const styleElements = doc.querySelectorAll('style');
    styleElements.forEach((element) => {
      if (element.parentNode) {
        element.parentNode.removeChild(element);
      }
    });

    // Remove all inline style attributes
    const allElementsWithStyle = doc.querySelectorAll('*');
    allElementsWithStyle.forEach((element) => {
      element.removeAttribute('style');
    });

    // Remove all link tags
    const linkElements = doc.querySelectorAll('link');
    linkElements.forEach((element) => {
      if (element.parentNode) {
        element.parentNode.removeChild(element);
      }
    });

    // Remove all script tags
    const scriptElements = doc.querySelectorAll('script');
    scriptElements.forEach((element) => {
      if (element.parentNode) {
        element.parentNode.removeChild(element);
      }
    });

    // Replace all SVG elements with placeholders
    const svgElements = doc.querySelectorAll('svg');
    svgElements.forEach((element) => {
      if (element.parentNode) {
        // Create a placeholder element
        const placeholder = doc.createElement('span');
        placeholder.textContent = '[SVG Icon]';
        placeholder.setAttribute('data-placeholder', 'svg-icon');

        // Replace SVG element
        element.parentNode.replaceChild(placeholder, element);
      }
    });

    // Replace all SVG images and objects
    const svgImages = doc.querySelectorAll(
      'img[src$=".svg"], object[data$=".svg"], embed[src$=".svg"]',
    );
    svgImages.forEach((element) => {
      if (element.parentNode) {
        // Create a placeholder element
        const placeholder = doc.createElement('span');
        placeholder.textContent = '[SVG Image]';
        placeholder.setAttribute('data-placeholder', 'svg-image');
        if (element.alt) {
          placeholder.textContent = `[SVG Image: ${element.alt}]`;
        }

        // Replace SVG image element
        element.parentNode.replaceChild(placeholder, element);
      }
    });

    // Remove elements with only data-* attributes, no children, and no class or style
    const allElements = Array.from(doc.querySelectorAll('*'));
    allElements.forEach((element) => {
      // Check if element has only data-* attributes
      let hasOnlyDataAttributes = true;
      let hasDataAttribute = false;

      // Check all attributes
      for (let i = 0; i < element.attributes.length; i++) {
        const attr = element.attributes[i];
        if (attr.name.startsWith('data-')) {
          hasDataAttribute = true;
        } else if (attr.name !== 'id') {
          // Allow id attribute
          hasOnlyDataAttributes = false;
          break;
        }
      }

      // If element has only data-* attributes, no children, and no text content
      if (
        hasOnlyDataAttributes &&
        hasDataAttribute &&
        element.children.length === 0 &&
        element.textContent.trim() === ''
      ) {
        // Remove the element
        if (element.parentNode) {
          element.parentNode.removeChild(element);
        }
      }
    });

    // Remove all HTML comments
    const removeComments = (node) => {
      const childNodes = node.childNodes;
      for (let i = childNodes.length - 1; i >= 0; i--) {
        const child = childNodes[i];
        if (child.nodeType === 8) {
          // Comment node
          node.removeChild(child);
        } else if (child.nodeType === 1) {
          // Element node
          removeComments(child);
        }
      }
    };
    removeComments(doc);

    // Return cleaned HTML
    return new XMLSerializer().serializeToString(doc);
  }

  // Interactive elements feature has been removed

  // Selector generation feature has been removed
}
